The longest waiting game in software history comes to an end today. But the frenzy has just begun.

Microsoft Windows 95, possibly the most heavily promoted computer product ever, officially went on sale throughout the Triangle at midnight.

The newest version of Microsoft’s highly successful operating system should make personal computers easier to set up and use. Windows 95 will include better audio and video capabilities, and offer easy access to the Internet through the Microsoft Network, the company’s new online service.

Seven to nine million copies are expected to be sold this week alone, according to market research firm Dataquest Inc. Another 20 million copies should be sold by the end of the year.

And those figures may be dwarfed next year. Concerned about possible bugs in the system, many users are expected to wait for a later version of Windows 95 before plunking down $90 for a copy. Also, sellers of computer systems and hardware are expected to see a sales spurt as users realize they need new, or at least upgraded, systems to run the new program.

But Microsoft isn’t leaving things to chance. It is spending $200 million on the launch, which has riveted the world’s attention. The purchase of the first copy — by a student in Auckland, New Zealand, seventeen hours before copies went on sale in the United States — drew extensive news coverage. More than 70,000 people are expected to attend launch events in 43 cities today. Microsoft paid a reported $4 million to license the rights to the Rolling Stones song "Start Me Up" for Windows 95 commercials.

More Mac than Mac?:

Windows 95, like all operating systems, is the software that determines how files are stored and different programs interact. The Microsoft empire was built on MS-DOS, the operating system that became the industry standard when IBM selected it in 1981 for its first personal computer. The two partners went their separate ways in 1985 when Microsoft introduced the original version of Windows, while IBM bet on an operating system known as OS/2 as a successor to DOS.

Windows found a following, but sales of OS/2 have languished. Nearly 80 percent of the world’s personal computers now run Microsoft operating software.

OS/2 may not be the only casualty. For many months, Windows 95 was known to the computer world only by its code name, "Chicago." But it might have better been named "William Tell," for Windows 95 could be an Apple-killer.

Windows 95 is supposed to make your PC more like a Macintosh. And some industry experts predict it may put the Macintosh out of business. With new features like longer file names and "plug-and-play" technology, a PC for the first time approaches the ease of use that made Macintoshes famous — but at a far lower cost.

Retailers such as Egghead Software in Cary started selling the software as soon as their clocks struck — or, in this digital age, beeped — midnight.

Tim Brown, an automation specialist at the Wake County Public Safety department, has paid $10 at Babbages in Cary Towne Center to reserve his copy.

"I’ll probably go pick it up in the afternoon," he said. "When people ask me whether it’s worth it, at least I’ll have some firsthand experience."

Egghead opened at 11 p.m. Wednesday to give customers a chance to browse. Then at midnight, copies went on sale. With Microsoft’s estimated installation time of 45 to 60 minutes, Triangle computer users could have had the software up and running by 1 a.m.

"We’ve had midnight madness events before and had very good turnout," Egghead manager Joe Mauk said Wednesday. "I really expect the store will be bursting at the seams. There may even be a line to get in."

More than 500 people have reserved copies so far, Mauk said. He had his full staff of 14 on hand until a 2 a.m. close. He plans to reopen the store at 7 this morning and stay on the job until 10 p.m.

A world of publicity:

As part of the launch, Microsoft will throw an invitation-only bash today featuring an hour long satellite address by CEO Bill Gates that will be seen by several hundred Triangle business executives and software developers at the Raleigh Civic and Convention Center.

"For all the hype we’ve heard, this is a good chance to actually see it," said Doug Haynes, a spokesman for Centura Bank in Rocky Mount, which will demonstrate online banking services that it plans to offer with Microsoft.

Other publicity stunts are a little more … … well, innovative.

Passengers flying from RDU to London should be sure to keep close to their airplane’s windows. Microsoft has painted fields in England with the Windows 95 logo so that they are visible from the air.

Four thousand boxes of Cracker Jacks will be given away with Windows 95 prizes inside in Chicago. The mayor of Fort Worth, Texas, will "officially upgrade" the city to Windows 95 in a ceremony today. Microsoft will pay for the entire press run of the Times of London — which will contain a Windows advertisement on the front page — and will give it away free, the first time in the newspaper’s history.

In New York, the Empire State Building will be lit in Microsoft colors this evening. In Toronto, the city’s tallest building, the CN Tower, will boast a 300-foot high Windows 95 banner. In Poland, journalists will be taken down in submarines to show them what it’s like to live "in a world without Windows."

The launch has become so much of an international event that Quebec Premier Jacques Parizeau issued a statement protesting delays in a special French Canadian version.

"We want to be there for the revolution," an aide told Bloomberg Business News. "And we want to be able to do it in our own language."

Until a few weeks ago, however, it wasn’t certain that the revolution would happen.

Microsoft first announced that the software would ship last year. As the company repeatedly pushed back the launch date, analysts began to wonder publicly whether the product was "vaporware," or software that is announced — usually to deter a competitor — but never reaches the market. An oft-repeated joke was that by the time it was ready, Windows 95 would have to be renamed Windows 96.

Then the Department of Justice threatened to intervene to stop distribution. Regulators were concerned that Microsoft had an unfair advantage in the online service market by making its online access available through Windows 95. The Microsoft Network is expected to draw 9 million users, almost triple the subscribers of CompuServe, the largest online service.

But the feds decided to not delay the rollout, and it came off on schedule. Although the anticipated reception has made Microsoft executives happy, it likely will make computer hardware manufacturers even happier.

To take advantage of the features, users will need more muscular computers than most of them now possess.

At least 39 percent of PC users will have to upgrade their computers to run Windows 95, according to a recent survey, and another 22 percent have barely enough power to enjoy its full benefits.

Virtually the only institution unimpressed with the hoopla was Wall Street. Microsoft stock closed at $97.875, down $1.438, in Nasdaq trading Wednesday.